艾比湖流域土壤有机质垂直空间变异特征

利用沿土壤深度方向的垂直滞后空间相关系数和经验正交函数分解方法研究了新疆艾比湖流域土壤有机质含量的垂直空间分布结构。结果表明:垂直滞后空间相关系数和经验正交函数分解方法能够有效分析空间区域土壤有机质垂直分布的相关性和空间异质性；垂直滞后空间正相关或负相关的集聚区域指示了相似或相反的有机质垂直分布模式，并且土壤有机质含量相关性随土层深度间隔增大而衰减；流域不同区域土壤有机质沿土层深度的垂直分布呈现分异特征，流域东部和西部地区有机质含量随土层深度增加而升高，但中部区域有机质含量随土层加深而降低，而且土壤有机质含量沿垂直方向递增或递减的速率在流域内亦表现出空间异质性。

Characteristics of the Vertical Distribution and Spatial Variability of Soil Organic Matter in Ebinur Lake Basin of Xinjiang Autonomous Region,China

The vertical space distribution patterns of soil organic matter(SOM) in Ebinur Lake Basin were investigated by using the vertical-lag spatial correlation and empirical orthogonal function analysis (EOF). The results show that the vertical-lag spatial positive correlation (negative correlation) can indicate the regions where SOM has a similar (contrary) vertical distribution pattern. Specifically, the SOM content displays an increasing trend with increase of soil depth in the eastern and western regions of Ebinur Lake Basin, but the SOM content decreases with the increase of soil depth in the central part of the basin. The SOM content within the 40 cm interval of soil layers is strong correlation, but it is a weak correlation when the interval of soil layer is more than 40 cm. There is a threshold along the vertical direction of soil (i.e. 60 cm) where the SOM content increment (decrement) rate is very different. In Ebinur Lake Basin, the vertical spatial variability of SOM was severely affected by the spatial variation of the watershed ecological environment, ecological landscape, the rhizodeposition characteristics of arid vegetation and the spatial heterogeneity of soil profile evolution.